1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <algorithm>
18 #include <ostream>
19 
20 #include "compiled_method_storage.h"
21 
22 #include "base/logging.h"
23 #include "compiled_method.h"
24 #include "thread-inl.h"
25 #include "utils.h"
26 #include "utils/dedupe_set-inl.h"
27 #include "utils/swap_space.h"
28 
29 namespace art {
30 
31 namespace {  // anonymous namespace
32 
33 template <typename T>
CopyArray(SwapSpace * swap_space,const ArrayRef<const T> & array)34 const LengthPrefixedArray<T>* CopyArray(SwapSpace* swap_space, const ArrayRef<const T>& array) {
35   DCHECK(!array.empty());
36   SwapAllocator<uint8_t> allocator(swap_space);
37   void* storage = allocator.allocate(LengthPrefixedArray<T>::ComputeSize(array.size()));
38   LengthPrefixedArray<T>* array_copy = new(storage) LengthPrefixedArray<T>(array.size());
39   std::copy(array.begin(), array.end(), array_copy->begin());
40   return array_copy;
41 }
42 
43 template <typename T>
ReleaseArray(SwapSpace * swap_space,const LengthPrefixedArray<T> * array)44 void ReleaseArray(SwapSpace* swap_space, const LengthPrefixedArray<T>* array) {
45   SwapAllocator<uint8_t> allocator(swap_space);
46   size_t size = LengthPrefixedArray<T>::ComputeSize(array->size());
47   array->~LengthPrefixedArray<T>();
48   allocator.deallocate(const_cast<uint8_t*>(reinterpret_cast<const uint8_t*>(array)), size);
49 }
50 
51 }  // anonymous namespace
52 
53 template <typename T, typename DedupeSetType>
AllocateOrDeduplicateArray(const ArrayRef<const T> & data,DedupeSetType * dedupe_set)54 inline const LengthPrefixedArray<T>* CompiledMethodStorage::AllocateOrDeduplicateArray(
55     const ArrayRef<const T>& data,
56     DedupeSetType* dedupe_set) {
57   if (data.empty()) {
58     return nullptr;
59   } else if (!DedupeEnabled()) {
60     return CopyArray(swap_space_.get(), data);
61   } else {
62     return dedupe_set->Add(Thread::Current(), data);
63   }
64 }
65 
66 template <typename T>
ReleaseArrayIfNotDeduplicated(const LengthPrefixedArray<T> * array)67 inline void CompiledMethodStorage::ReleaseArrayIfNotDeduplicated(
68     const LengthPrefixedArray<T>* array) {
69   if (array != nullptr && !DedupeEnabled()) {
70     ReleaseArray(swap_space_.get(), array);
71   }
72 }
73 
74 template <typename ContentType>
75 class CompiledMethodStorage::DedupeHashFunc {
76  private:
77   static constexpr bool kUseMurmur3Hash = true;
78 
79  public:
operator ()(const ArrayRef<ContentType> & array) const80   size_t operator()(const ArrayRef<ContentType>& array) const {
81     const uint8_t* data = reinterpret_cast<const uint8_t*>(array.data());
82     // TODO: More reasonable assertion.
83     // static_assert(IsPowerOfTwo(sizeof(ContentType)),
84     //    "ContentType is not power of two, don't know whether array layout is as assumed");
85     uint32_t len = sizeof(ContentType) * array.size();
86     if (kUseMurmur3Hash) {
87       static constexpr uint32_t c1 = 0xcc9e2d51;
88       static constexpr uint32_t c2 = 0x1b873593;
89       static constexpr uint32_t r1 = 15;
90       static constexpr uint32_t r2 = 13;
91       static constexpr uint32_t m = 5;
92       static constexpr uint32_t n = 0xe6546b64;
93 
94       uint32_t hash = 0;
95 
96       const int nblocks = len / 4;
97       typedef __attribute__((__aligned__(1))) uint32_t unaligned_uint32_t;
98       const unaligned_uint32_t *blocks = reinterpret_cast<const uint32_t*>(data);
99       int i;
100       for (i = 0; i < nblocks; i++) {
101         uint32_t k = blocks[i];
102         k *= c1;
103         k = (k << r1) | (k >> (32 - r1));
104         k *= c2;
105 
106         hash ^= k;
107         hash = ((hash << r2) | (hash >> (32 - r2))) * m + n;
108       }
109 
110       const uint8_t *tail = reinterpret_cast<const uint8_t*>(data + nblocks * 4);
111       uint32_t k1 = 0;
112 
113       switch (len & 3) {
114         case 3:
115           k1 ^= tail[2] << 16;
116           FALLTHROUGH_INTENDED;
117         case 2:
118           k1 ^= tail[1] << 8;
119           FALLTHROUGH_INTENDED;
120         case 1:
121           k1 ^= tail[0];
122 
123           k1 *= c1;
124           k1 = (k1 << r1) | (k1 >> (32 - r1));
125           k1 *= c2;
126           hash ^= k1;
127       }
128 
129       hash ^= len;
130       hash ^= (hash >> 16);
131       hash *= 0x85ebca6b;
132       hash ^= (hash >> 13);
133       hash *= 0xc2b2ae35;
134       hash ^= (hash >> 16);
135 
136       return hash;
137     } else {
138       size_t hash = 0x811c9dc5;
139       for (uint32_t i = 0; i < len; ++i) {
140         hash = (hash * 16777619) ^ data[i];
141       }
142       hash += hash << 13;
143       hash ^= hash >> 7;
144       hash += hash << 3;
145       hash ^= hash >> 17;
146       hash += hash << 5;
147       return hash;
148     }
149   }
150 };
151 
152 template <typename T>
153 class CompiledMethodStorage::LengthPrefixedArrayAlloc {
154  public:
LengthPrefixedArrayAlloc(SwapSpace * swap_space)155   explicit LengthPrefixedArrayAlloc(SwapSpace* swap_space)
156       : swap_space_(swap_space) {
157   }
158 
Copy(const ArrayRef<const T> & array)159   const LengthPrefixedArray<T>* Copy(const ArrayRef<const T>& array) {
160     return CopyArray(swap_space_, array);
161   }
162 
Destroy(const LengthPrefixedArray<T> * array)163   void Destroy(const LengthPrefixedArray<T>* array) {
164     ReleaseArray(swap_space_, array);
165   }
166 
167  private:
168   SwapSpace* const swap_space_;
169 };
170 
CompiledMethodStorage(int swap_fd)171 CompiledMethodStorage::CompiledMethodStorage(int swap_fd)
172     : swap_space_(swap_fd == -1 ? nullptr : new SwapSpace(swap_fd, 10 * MB)),
173       dedupe_enabled_(true),
174       dedupe_code_("dedupe code", LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
175       dedupe_src_mapping_table_("dedupe source mapping table",
176                                 LengthPrefixedArrayAlloc<SrcMapElem>(swap_space_.get())),
177       dedupe_vmap_table_("dedupe vmap table",
178                          LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
179       dedupe_cfi_info_("dedupe cfi info", LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
180       dedupe_linker_patches_("dedupe cfi info",
181                              LengthPrefixedArrayAlloc<LinkerPatch>(swap_space_.get())) {
182 }
183 
~CompiledMethodStorage()184 CompiledMethodStorage::~CompiledMethodStorage() {
185   // All done by member destructors.
186 }
187 
DumpMemoryUsage(std::ostream & os,bool extended) const188 void CompiledMethodStorage::DumpMemoryUsage(std::ostream& os, bool extended) const {
189   if (swap_space_.get() != nullptr) {
190     const size_t swap_size = swap_space_->GetSize();
191     os << " swap=" << PrettySize(swap_size) << " (" << swap_size << "B)";
192   }
193   if (extended) {
194     Thread* self = Thread::Current();
195     os << "\nCode dedupe: " << dedupe_code_.DumpStats(self);
196     os << "\nVmap table dedupe: " << dedupe_vmap_table_.DumpStats(self);
197     os << "\nCFI info dedupe: " << dedupe_cfi_info_.DumpStats(self);
198   }
199 }
200 
DeduplicateCode(const ArrayRef<const uint8_t> & code)201 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateCode(
202     const ArrayRef<const uint8_t>& code) {
203   return AllocateOrDeduplicateArray(code, &dedupe_code_);
204 }
205 
ReleaseCode(const LengthPrefixedArray<uint8_t> * code)206 void CompiledMethodStorage::ReleaseCode(const LengthPrefixedArray<uint8_t>* code) {
207   ReleaseArrayIfNotDeduplicated(code);
208 }
209 
DeduplicateSrcMappingTable(const ArrayRef<const SrcMapElem> & src_map)210 const LengthPrefixedArray<SrcMapElem>* CompiledMethodStorage::DeduplicateSrcMappingTable(
211     const ArrayRef<const SrcMapElem>& src_map) {
212   return AllocateOrDeduplicateArray(src_map, &dedupe_src_mapping_table_);
213 }
214 
ReleaseSrcMappingTable(const LengthPrefixedArray<SrcMapElem> * src_map)215 void CompiledMethodStorage::ReleaseSrcMappingTable(const LengthPrefixedArray<SrcMapElem>* src_map) {
216   ReleaseArrayIfNotDeduplicated(src_map);
217 }
218 
DeduplicateVMapTable(const ArrayRef<const uint8_t> & table)219 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateVMapTable(
220     const ArrayRef<const uint8_t>& table) {
221   return AllocateOrDeduplicateArray(table, &dedupe_vmap_table_);
222 }
223 
ReleaseVMapTable(const LengthPrefixedArray<uint8_t> * table)224 void CompiledMethodStorage::ReleaseVMapTable(const LengthPrefixedArray<uint8_t>* table) {
225   ReleaseArrayIfNotDeduplicated(table);
226 }
227 
DeduplicateCFIInfo(const ArrayRef<const uint8_t> & cfi_info)228 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateCFIInfo(
229     const ArrayRef<const uint8_t>& cfi_info) {
230   return AllocateOrDeduplicateArray(cfi_info, &dedupe_cfi_info_);
231 }
232 
ReleaseCFIInfo(const LengthPrefixedArray<uint8_t> * cfi_info)233 void CompiledMethodStorage::ReleaseCFIInfo(const LengthPrefixedArray<uint8_t>* cfi_info) {
234   ReleaseArrayIfNotDeduplicated(cfi_info);
235 }
236 
DeduplicateLinkerPatches(const ArrayRef<const LinkerPatch> & linker_patches)237 const LengthPrefixedArray<LinkerPatch>* CompiledMethodStorage::DeduplicateLinkerPatches(
238     const ArrayRef<const LinkerPatch>& linker_patches) {
239   return AllocateOrDeduplicateArray(linker_patches, &dedupe_linker_patches_);
240 }
241 
ReleaseLinkerPatches(const LengthPrefixedArray<LinkerPatch> * linker_patches)242 void CompiledMethodStorage::ReleaseLinkerPatches(
243     const LengthPrefixedArray<LinkerPatch>* linker_patches) {
244   ReleaseArrayIfNotDeduplicated(linker_patches);
245 }
246 
247 }  // namespace art
248